Yellow Fever study

Shortage of Yellow Fever vaccines: what solution in the event of an outbreak?

The MSF Foundation is supporting a study run by Epicentre to demonstrate the effectiveness of fractional dosing of the Yellow Fever vaccine and initiate a large-scale change of practice in the event of an outbreak.

/ Field findings.Yellow Fever is one of the most serious infectious disease threats in the world,yet only four pharmaceutical companies produce the Yellow Fever vaccine. As a result, there are frequent shortages.

/ Response.On the basis of data gathered through field research, confirm that one fifth of the regular dose of Yellow Fever vaccine provides the same immunity as a full dose.

Yellow Fever -This is an acute viral haemorrhagic disease transmitted by infected mosquitoes. There is no treatment for this disease. Immunisation is the only way of preventing it.

50 000 victims-According to WHO, Yellow Fever kills more than 50,000 people in Africa every year. In eight months (from December 2015 to August 2016) 500 people died of this desease in Angola and the Democratic Republic of Congo (DRC).

6 million doses of vaccine-This is the total number of doses produced each year. A recent epidemic has used up much of this year’s stock. In the event of a further outbreak, there is a danger of running out of vaccine.

Preliminary results

Initial results are encouraging: 960 participants have joined the research project and 99.1% of them came to the follow-up visit 28 days after being vaccinated. Outreach teams are in constant contact with the communities targeted by the study through regular visits.

Aitana Juan, the study’s principal Investigator

Why only use fractional dosing in periods of crisis? “ At the moment, we don’t know enough about the length of immunity provided by a fractional dose. However, we do know that a full dose confers life-long protection.”

Participants

When participants arrive at the study site, the medical personnel explain the study to them and a doctor makes sure they can be given the vaccine. The project team sees around a dozen participants a day.